A loudspeaker or speaker is an electroacoustic transducer that converts an electronic audio signal into a corresponding sound. For example, a loudspeaker can include a magnet and a voice coil, which can be attached to a diaphragm. When an electronic signal is applied to the voice coil, a magnetic field can be created by the electric current in the voice coil, making it a variable electromagnet, which can interact with the field of the magnet to generate mechanical force that causes the voice coil and thus the attached diaphragm to move and produce audio frequencies under the control of the applied signal.